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I found out that the Content.mcgb is actually a little GUI helper and you can generate and easily load a .spritefont file with it.
Steps:
1.Load the GUI app by double clicking the "Content.mcgb" file in the "Content" folder
2.Go to Edit -> New Item... -> Choose SpriteFont and give it a name -> Hit "Ok"
3.Go to Build -> Build (or hit F6) - You should get ...

You don't want to turn off depth stencil state. Leave that the way it was before.
Giving the Problem a Name
The problem you're having is that two objects are being drawn in almost identical locations, but because of floating point precision errors, at the different pixels, sometimes one turns out to be barely closer to the camera/eye than the other, and on ...

I avoid Euler angles in aircraft pitch, roll, yaw orientations because aircraft rotate about thier local axis and trying to resolve this to Euler angles about the world (or global) axis adds uneccesary complication to the code. Instead of 3 Euler angles, I store the current orientation as a matrix or quat and simply modify the matrix/quat depending on input ...

You're using vector3.up, vector3.forward and vector3.right to calculate the needed rotations. These axes don't move along with your plane. What you need to do is rotate the plane around its very own up, forward and right vectors. You could do that like this:
Matrix rotMat = Matrix.CreateFromQuaternion(model_ROTATION);
Quaternion additionalRotation = ...